Method and apparatus for producing a synthetic tensile member with a precise length and enhanced stability

ABSTRACT

A method for producing a synthetic tensile member having a precisely known and stable length. The invention also comprises equipment configured to carry out the method. A tensile member is prepared by attaching terminations to an assembly of synthetic filaments. The tensile member is then attached to a loading apparatus that subjects the tensile member to a pre-defined loading process. The tensile member is thereby conditioned to a stable length. The length is then measured and a length adjusting component is incorporated into the tensile member to create a precise and stabilized length that is configured for the tensile member&#39;s particular application.

CROSS-REFERENCES TO RELATED APPLICATIONS

This non-provisional patent application is a continuation of U.S. patentapplication Ser. No. 16/994,859, which is itself a continuation of U.S.patent application Ser. No. 15/616,385 (now U.S. Pat. No. 10,745,856).The parent applications listed the same inventor.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

MICROFICHE APPENDIX

Not Applicable

BACKGROUND OF THE INVENTION 1. Field of the Invention

This invention relates to the field of tensile strength members such asmulti-stranded synthetic cables. More specifically, the inventioncomprises devices and methods for creating a synthetic tensile memberhaving a fixed and stable length.

2. Description of the Related Art

The term “tensile member” encompasses a very broad range of knowndevices, including steel rods, helically wrapped wire ropes/cables,fiber ropes/cables, wound slings, rope slings grommets, etc. Thesedevices have for many years been made using steel. For a fixedinstallation—such as a bridge stay—a relatively rigid rod may be used.For a more mobile or dynamic installations—such as the rigging on theboom of a crane—helically wrapped wire rope may be used. Steel tensilemembers have been mass produced for over one hundred years and theproperties of these tensile members are very well understood. Forexample, it is well understood how to manufacture a steel tensile memberto a precise level of performance and a precise overall length.

Such wire ropes may need to be “set” or “bedded” when they are firstassembled. This process involves applying tension to tighten theinterwoven nature of the strands within the rope. An initial “stretch”will occur, after which a wire rope remains in the “set” state.Significantly, the amount of set needed is predictable. It is thereforepossible to create a wire rope that is “short” by a calculated amount sothat when the wire rope is set it will lengthen by a known amount andwind up being the proper length.

A termination must generally be added to a tensile member in order totransmit a load into or out of the tensile member. A terminations ismost commonly affixed to the end of a tensile member, though it can beaffixed to an intermediate point as well. In this context, the term“termination” means a structure that is affixed to the tensile member(or otherwise caused to become present on the tensile member) totransmit a load to or from the tensile member. The term encompassessolid anchors, soft splices, and round grommet or sling structures. Theterm also includes terminations that may be incorporated on asubcomponent of a larger tensile member, such as a sub-rope or strand.

As stated previously, wire rope is an example of a steel tensile member.A hook or loading eye is often added to wire rope. The hook or loadingeye in this context is a termination. Such prior art terminations onlarge wire ropes commonly include a socket. A length of the wire rope isplaced within the socket and “upset” into an enlarged diameter. Theupset portion is then potted into the socket using molten lead or—morerecently—a strong epoxy. Once the potted portion solidifies, the end ofthe wire rope is locked into the socket and the termination is therebypermanently affixed.

In recent years materials much stronger than steel have become availablefor use in the construction of cables and other tensile strengthmembers. Many different materials are used for the filaments in asynthetic cable. These include DYNEEMA, SPECTRA, TECHNORA, TWARON,KEVLAR, VECTRAN, PBO, carbon fiber, nano-tubes, and glass fiber (amongmany others). In general the individual filaments have a thickness thatis less than that of human hair. The filaments are very strong intension, but they are not very rigid. They also tend to have low surfacefriction. These facts make such synthetic filaments difficult to handleduring the process of adding a termination and difficult to organize.The present invention is particularly applicable to terminated tensilemembers made of such high-strength synthetic filaments, for reasonswhich will be explained in the descriptive text to follow. While theinvention could in theory be applied to older cable technologies—such aswire rope—it likely would offer little advantage for that application.Thus, the invention is not really applicable to wire rope and othersimilar cables made of very stiff elements.

In this disclosure the term “synthetic tensile member” should beunderstood to encompass a tensile member made primarily of syntheticfilaments. However, it should be understood that other traditionalconstituents (such as metallic strands) may be present in these“synthetic” cables as well. Synthetic tensile member is also intended toapply to subcomponents of larger assemblies or tensile members, such asthe sub-rope or strand of a large rope/cable. Additionally, the terms“rope” and “cable” will be used interchangeably—as they are both commonindustry terms that apply to nearly all structural materials.

The present invention is applicable to many different types of tensilemembers (not just cables). However, because cables are a very commonapplication and because the inventive principles will be the same acrossthe differing types of tensile members, cables are used in thedescriptive embodiments. Some terminology used in the construction ofcables will therefore benefit the reader's understanding, though it isimportant to know that the terminology varies within the industry andeven varies within descriptive materials produced by the samemanufacturer. For purposes of this patent application, the smallestindividual component of a cable is known as a “filament.” A filament isoften created by an extrusion process (though others are used). Manyfilaments are grouped together to create a strand. The filaments arebraided and/or twisted together using a variety of known techniques inorder to create a cohesive strand. There may also be sub-groups offilaments within each strand. As the overall cable size gets larger,more and more layers of filament organization will typically be added.The strands are typically braided and/or twisted together to form acable. In other examples the strands may be purely parallel and encasedin individual surrounding jackets. In still other examples the strandsmay be arranged in a “cable lay” pattern that is well known in thefabrication of wire ropes.

The inventive principles to be disclosed may be applied to an individualstrand. They may also be applied to an entire cable made up of manystrands. Thus, the invention may be applied to a completed tensilemember and it may be applied to a component of an overall tensile memberbefore the component is installed into the final assembly.

FIGS. 1-4 provide some background materials to aid the reader'sunderstanding. FIG. 1 depicts a very simple cable 10 that is made ofthree helically wrapped strands 12. Each strand 12 contains many, manyindividual filaments. FIG. 2 shows the cable of FIG. 1 with atermination 36 attached. Anchor 18 in this example is a radiallysymmetric component with an expanding central passage 19. A length ofthe cable is placed in this expanding internal passage and splayedapart. Potting compound is introduced into the passage in a liquidstate. The potting compound is any substance which transitions from aliquid to a solid over time (such as an epoxy). The potting compoundhardens to form potted region 20. Once the potted region is formed,anchor 18 is locked to the end of cable 10 and a termination 36 isthereby created.

In other examples the cable will be locked to the anchor without the useof a potting compound. Those skilled in the art will know thatfrictional devices (such as a “spike-and-cone” system) can be used tolock the anchor to the cable). In still other examples the anchor willbe formed as a splice in which an end of the cable is formed into a loopand woven back into itself.

FIG. 3 provides an example with a more complex organization. Cableassembly 30 includes three individual cables 10 within an encompassingjacket 28. An anchor 18 is affixed to the end of each cable 10.Collector 22 includes three receivers 26—each of which is configured toreceive an anchor 18. The anchors are connected to collector 22 and aload transferring feature 24 (shown using hidden lines) transferstension from collector 22 to an external component.

FIG. 4 shows another example using three parallel cables 10. Each cable10 includes a termination 36. The three terminations 36 are connected toloading block 32 using a pin joint. This example illustrates the needfor uniformity and predictability of the length of the three cables. Ifone of the cables is slightly shorter, it will carry a disproportionallyhigher share of the overall load.

Producing synthetic tensile members with a consistent and predictableoverall length is presently a serious industry challenge. The problemsresult from one or more of the following factors:

1. The mechanical properties of synthetic filaments vary from batch tobatch. While this is true of more traditional materials, the variance issynthetic materials is much greater;

2. Most strands or cables must be created by braiding together thousandsto millions of individual synthetic filaments. Two braiding orinterweaving machines may appear to produce a similar result but in factthe properties will vary;

3. There are many steps in fabricating a completed cable assembly usingsynthetic filaments. Each step introduces additional variations andthese variations tend to accumulate;

4. Synthetic filaments must generally be elastically bent and interwovenduring the manufacturing process. These filaments have a low coefficientof friction, and since they are not stiff they are designed to move and“bed” during use. This bedding or setting process changes both themechanical properties of a cable as a whole (such as the modulus ofelasticity) and the overall length;

5. Synthetic filaments are temperature sensitive. This fact affectsstiffness and length in the normal working range; and

6. The addition of a termination to a cable end introduces aconsiderable slip variable (“setting” or “bedding”) when the cableassembly is first loaded. This variable increases the overall cablelength, but the amount of increase has proved to be unpredictable. Thisis especially the case with friction or grip based termination methods,such as a splice (which is the most common method of synthetic cabletermination).

All these issues tend to grow more significant as a cable assemblyincreases in length, strength, and complexity. It is difficult topredict the behavior of larger tensile members due to the accumulationof manufacturing tolerances for all the subcomponents. Further, it maybe some time before the length becomes stable as the length of somecable assemblies may continue to grow under tension as the interworkingelements stabilize. If such a tension member is combined in parallelwith other tension members, an uneven distribution of the overall loadresults.

For these reasons, it is not presently common to use synthetic cableswhere a precise length or stability is important. Exemplary applicationsinclude large crane boom stays, bridge stays, and multi-point liftingslings or multi-cable bridle assemblies Because of the enormous loadsinvolved, it is common to use a parallel assembly of four or more cablesin these applications.

There are length-adjusting mechanisms known in the prior art. Oneexample is a large turnbuckle. It is rarely practical to include such alarge and heavy item. Further, a turnbuckle does not remedy the concernsof length or load stability unless it is periodically readjusted (Aturnbuckle must be initially tensioned and then periodicallyre-tensioned as the cable “sets”). A suitable turnbuckle will alsorequire a substantial torque to adjust, and it is often difficult toapply such a large amount of torque in the field. One may imagine aturnbuckle on a dragline crane that is 50 meters in the air. Adjustingsuch a turnbuckle would not be easy. Further, an improper adjustment maypermanently damage the boom if not properly matched with adjustments tothe other cables.

The present invention seeks to remedy both the problem of lengthconsistency and the problem of length stability. The invention solvesthese problems across all types of synthetic filament-based tensilemembers and termination methods—without the need for a field adjustmentdevice.

BRIEF SUMMARY OF THE PRESENT INVENTION

The present invention comprises a method for producing a syntheticfilament tensile member having a precisely known and stable length. Theinvention also comprises equipment configured to carry out the method. Atensile member is prepared by attaching terminations to an assembly ofsynthetic filaments. The tensile member is then attached to a loadingapparatus that subjects the tensile member to a pre-defined loadingprocess. The tensile member is thereby conditioned to a stable length.The length is then measured and a length adjusting component is added tothe tensile member (or a suitable modification is made to the tensilemember) to create a precise length that is configured for the tensilemember's particular application.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a perspective view, showing a prior art cable made of threewrapped strands.

FIG. 2 is a sectional elevation view, showing one way in which atermination can be attached to a cable.

FIG. 3 is a perspective view, showing a cable termination in whichmultiple anchors are attached to a collector.

FIG. 4 is a perspective view, showing a parallel cable assembly.

FIG. 5 is an elevation view, showing a tensioning rig employed in thepresent invention.

FIG. 6 is a perspective view, showing the addition of an extension link.

FIG. 7 is a perspective view, showing the use of an extended tang.

FIG. 8 is an elevation view, showing a splice-based termination.

FIG. 9 is a sectional view, showing the nature of the thimble used inthe splice-based termination of FIG. 8 .

FIG. 10 is a perspective view, showing a thimble block.

FIG. 11 is an elevation and perspective view, showing a terminationhaving a threaded shaft and an extension bushing.

FIG. 12 is an elevation view, showing the placement of the extensionbushing on the threaded shaft.

FIG. 13 is a perspective view, showing the use of a plug in a loadingeye.

FIG. 14 is a perspective view, showing the addition of an extension linkto a spliced termination.

FIG. 15 is a perspective view, showing the use of a compressive bushing.

FIG. 16 is an elevation view, showing the use of a correction block.

FIG. 17 is an elevation view, showing the use of an extension link inthe middle of a cable assembly.

FIG. 18 is a plot showing applied tension over time.

REFERENCE NUMERALS IN THE DRAWINGS

10 cable

12 strand

18 anchor

19 passage

20 potted region

22 collector

24 load transferring feature

26 receiver

28 jacket

30 cable assembly

32 loading block

34 parallel assembly

36 termination

38 loading fixture

40 static fixture

42 extension link

44 first cross bore

45 first attachment reference

46 second cross bore

47 second attachment reference

48 tang

50 pin

52 first clevis

54 second clevis

56 extended tang

58 reference axis

60 cross bore

62 thimble

64 strands

66 jacket

68 thimble block

70 threaded shaft

72 extension bushing

74 mating surface

76 bearing surface

78 through bore

80 fusion

82 eye

84 cross bore

86 plug

88 offset cross bore

90 spliced eye

92 bushing half

94 correction block

96 overhang

DETAILED DESCRIPTION OF THE INVENTION

A cable made according to the present invention will generally have afirst termination on its first end and a second termination on itssecond end. The first termination will have a first attachmentreference—such as the center axis of a first cross bore through thefirst termination. The second termination will likewise have a secondattachment reference—such as the center axis of a second cross borethrough the second termination.

Returning to FIG. 4 , those skilled in the art will know that theparallel assembly of three cables will typically have a loading block 32or analogous anchoring component on each end. The example shown uses alarge transverse pin joint to connect the terminations 36 to the loadingblock 32. For this particular installation, there is a known distancebetween the pin joint axis on the loading block 32 shown and the pinjoint axis on the loading block on the opposite end of the cables. Thecables must match this known distance in order to be correctlyinstalled. In other words, the distance between the first and secondattachment references on the cables must be equal to the known distance.

FIG. 5 shows a synthetic cable assembly created by adding a termination36 to each end of cable 10. The first termination is connected to staticfixture 40. First attachment reference 45 on the first termination isthe center line of a pin joint used to attach the first termination tothe static fixture (Note that the first attachment reference could be atsome other point along the assembly and need not coincide with theattachment point).

The second termination is attached to loading fixture 38. Apredetermined tension profile is then applied through loading fixture38. Second attachment reference 47 on the second termination is thecenter line of a pin joint used to attach the second termination toloading fixture 38 (Note that the second attachment reference could beat some other point along the assembly and need not coincide with theattachment point).

This tension profile may assume many forms, but it is preferable toinclude a pull test to a higher load than is anticipated in the end-useapplication. Where practical, it is also preferable to include multiplepulls to better condition the cable.

FIG. 18 depicts an exemplary tension profile. The “design load”represents the maximum tension the cable assembly is expected to see inits upcoming installation. In this example, two ramped “pulls” are madeto a level exceeding the design load by 20%. A third pull is establishedwith a sinusoidal component applied over an extended period. With somefiber types, it is also beneficial to hold a load for a defined periodso that the fibers will permanently elongate and better distribute theload.

The tension profile is configured to fully “bed” (“set”) both theterminations and the lay of the cable itself. The length of the overallassembly will tend to extend for some period and then stabilize. Oncethe length has stabilized, the distance between the first attachmentreference on the first termination and the second attachment referenceon the second termination is determined. Two carefully pre-cut andterminated cable assemblies may have lengths that are very nearly thesame. However, the length variation will tend to grow with the beddingprocess.

This step may be accomplished in many ways. As one example, if the firstand second attachment references are simple cross bores through tangs onthe terminations, then closely fitted dowels can be placed in thesecross bores. The assembly can then be placed under a suitable tensionlevel and the distance between the dowels can be measured.

In many instances it will be desirable to design the cable andterminations so that the bedded cable assembly winds up being a bitshort. A length-adjustment component may then be added to bring theoverall assembly of the now-stabilized cable to the proper length. Thereare many ways to provide such a length-adjustment component. Thefollowing embodiments illustrate some of these ways.

FIG. 6 shows a second termination 36 on the second end of cable 10. Thetermination includes tang 48. A cross bore through the tang is used toattach the termination. The central axis of this cross bore is thesecond attachment reference used to determine the overall length of thecable assembly.

Extension link 42 is provided to increase the effective length of thecable assembly. The extension link includes first clevis 52 and secondclevis 54. The extension link also includes first cross bore 44 andsecond cross bore 46. First cross bore 44 is aligned with the cross borein tang 48 and pin 50 is inserted to connect the extension link to thesecond termination. Second cross bore 46 is offset a distance “D” fromfirst cross bore 44. In this example the second cross bore 46 becomes athird attachment reference. If one then measures the distance from thefirst attachment reference (on the opposite end of the cable) and thenew third attachment reference created by the presence of second crossbore 46, the overall length of the cable will be increased.

To improve accuracy, it is preferable to take the length measurementswhile the cable assembly is under a fixed reference load. The referenceload is preferably as close as possible to the load anticipated for theend-use application.

The process as applied in this exemplary embodiment may then besummarized as follows:

1. A known distance is the target value needed for the cable's desiredinstallation at the anticipated reference load;

2. The cable is created with an overall length that is marginally tooshort for the known distance and defined reference load;

3. The cable undergoes the setting process depicted in FIG. 5 ;

4. The distance between the first and second attachment references isaccurately determined;

5. An offset distance between the second attachment reference and adesired third attachment reference is calculated; and

6. An extension link 42 of suitable length is manufactured (or possiblypulled from inventory) and attached to the second termination, where theextension link provides the additional distance needed for the cable tohave the correct overall length.

Using exemplary numbers, the known distance for a particularinstallation is 30.260 meters. Once manufactured and set (as depicted inFIG. 5 ), the distance between the first and second attachmentreferences is carefully measured to be 29.900 meters. An extension linkis manufactured where the distance “D” between the first and secondcross bores 44, 46 is 0.360 meters. This extension link is theninstalled as shown in FIG. 6 . The cable assembly thus made now has theexact length desired (30.260 meters). And, the length is stable as thecable assembly has already been properly set. In this way countlessassemblies can be created to exacting specification with a length thatis stable and predictable over time.

FIG. 7 provides another embodiment in which the second termination 36 isprovided with an extended tang 56. Loading cross bore 59 is provided sothat the cable assembly can be attached to loading fixture 38 (asdepicted in FIG. 5 ). Once the loading process has been used to set thecable and its terminations, a second cross bore 60 is created inextended tang 56. In this example, both loading cross bore 59 and crossbore 60 are located with respect to reference axis 58. The cable isagain manufactured a bit short. Cross bore 60 is offset by a distance(D2-D1). Cross bore 60 then becomes the desired third attachmentreference and provides the correct overall length for the cable.

FIG. 8 shows a second termination 36 made using a splice. A spliceinvolves passing a length of cable around a thimble 62 and then weavingit back on itself. Such a termination can be very strong. However,because the interweaving is a highly-skilled manual process, itintroduces considerable uncertainty regarding the final length of thecable following the setting process depicted in FIG. 5 . While generallyimproved, similar process variation challenges are also involved inround slings, grommets, reeved cable block tension members, or woundslings. These types of looped tensile members will commonly include athimble of some sort for support of high loads.

FIG. 9 depicts a cross section through thimble 62. The reader will notehow the thimble in this example includes a concave channel configured toreceive the cable strands 64 (and jacket 66 in this case). The inwardfacing surface of thimble 62 is planar. In many cases thimble 62 maysimply be a pulley or sheave configuration with a central cross bore.

FIG. 10 depicts thimble block 68, which is configured to slide laterallyinto the thimble. When the thimble block is installed within the middleportion of the thimble, loading cross bore 59 allows the cable assemblyto be set as shown in FIG. 5 . Once a stable length is achieved adistance between the first and second attachment references isdetermined. An additional length required for the cable is determined.Cross bore 60 is then created in the thimble block. The additionallength needed will be equal to (D2-D1) in the depiction of FIG. 10 .Cross bore 60 then becomes the desired third attachment reference.

Up to this point the second and third attachment references have beenthe centerlines of cross bores. This will not always be the case, asthere are many different components used to attach terminations toexternal components. FIGS. 11 and 12 illustrate a different approach.

The second termination 36 in this example includes a long threaded shaft70. The cable assembly is attached to an external object by passingthreaded shaft 70 through a hole in a thick steel plate and thenthreading a nut onto the exposed end of the threaded shaft. The nut isthen tightened. Bearing surface 76 on termination 36 provides thedesired second attachment reference.

In this example—once the cable assembly is set as shown in FIG. 5 —thecable assembly's length is again too short. Extension bushing 72 isprovided to address this problem. Extension bushing 72 has matingsurface 74 and bearing surface 76 on its opposite end. It also includesthrough bore 78. Through bore 78 is slipped over threaded shaft 70 andmating surface 74 on extension bushing 72 is mated to bearing surface 76on termination 26.

The mated assembly is shown in FIG. 12 . Bearing surface 76 has therebybeen extended by the distance “D” to form the desired third attachmentreference. The two mating surfaces may be joined by adhesives, welding,or some other suitable method to create fusion 80. The termination andthe extension bushing thereafter behave as one integrated part. Wherepossible, it is desirable for the length adjustment part to bepermanent. The purpose of the fusion is simply to provide thispermanence.

FIG. 13 shows a second termination incorporating eye 82 and an enlargedcross bore 84. Plug 86 is configured to slide laterally into cross bore84. Offset cross bore 88 provides the desired third attachmentreference. It is offset from the center of plug 86 an appropriate amountto produce the desired overall length for the cable assembly.

FIG. 14 shows an embodiment where an extension link 42 is added to aspliced type of termination. A length of cable is wrapped around athimble and woven back into itself to create spliced eye 90. Theextension link is connected to this spliced eye by passing a lateral pinthrough the extension link and the spliced eye.

In the prior examples a cable that was marginally too short was extendedby the addition of a length-adjustment component. In other instances thecable will be made marginally too long and the length-adjustmentcomponent will need to shorten its effective length. FIG. 15 shows asecond termination 36 that includes a planar posterior bearing surfacewhere the cable exits the anchor. In this example two bushing halves 92have been clamped around the cable up against this posterior bearingsurface. The two bushing halves create bearing surface 76—effectivelyreducing the length of the cable. Bearing surface 76 then becomes thedesired third attachment reference. The reader should note that thistype of corrective bushing can be added to each of the individualanchors as shown in the example of FIG. 3 in order to apply a lengthcorrection to the entire cable (three bushing assemblies would berequired for the example of FIG. 3 ).

FIG. 16 shows a length-adjustment component used to increase or decreasethe effective cable length for the type of anchor shown in FIG. 15 .Correction block 94 includes a cavity to receive termination 36.Overhang 96 abuts the posterior bearing surface on the termination.Cross bore 60 is provided a distance “D” from the posterior bearingsurface. Thus, cross bore 60 extends the effective length of the cableassembly and provides the third attachment reference.

In the preceding examples the length-adjustment component has been addedto an end of the cable assembly. It is also possible to add thelength-adjustment component to an intermediate location. FIG. 17 showsan embodiment in which a third and fourth termination 36 have been addedin the middle of the cable. These third and fourth terminations cansimply be linked together for the tensioning process shown in FIG. 5 .An extension link 42 can then be added between the third and fourthterminations to increase the length of the cable assembly to match thedesired length.

Cables have been used as the examples in this disclosure, but the readershould bear in mind the fact that the principles disclosed apply to manyother types of tensile members. These include synthetic rope/cable/cordgrommets, choked assemblies, reeved block assemblies, and looped slingsor pendants where a loop of filaments, strands, or cables are woundaround two end points, and the two end points thereby becometerminations.

Additionally, the inventive process is not specific to the terminationtype/method or length correction component. The examples are merelymeant to represent a design based on certain termination configurations.These designs are not to be viewed as limiting, like that of the tensilemember, they will vary broadly from application to application—andcountless variations are possible.

The invention includes many other functional variations that are assumedthroughout the examples, such as:

1. An embodiment in which a length-adjustment component is added to bothends of the cable. In many applications this is preferable and should beassumed to be the case in all embodiments in this disclosure. Thesimplified depiction of a second termination receiving a lengthadjustment feature is simply meant to assume that at least one end, ifnot both ends receive such a component;

2. An embodiment in which multiple length-adjustment components are“stacked” or otherwise configured for use on at least one end of thecable;

3. An embodiment in which the length-adjustment component is simply amodification of a component already on the cable (such as milling away afinal load bearing surface or drilling a cross bore hole on thetermination body itself as examples);

4. An embodiment in which the length-adjustment component is tamperresistant so that it cannot be easily modified in the field;

5. An embodiment in which the length-adjustment component is madevisibly out of alignment should it be out of factory setting;

6. A configuration in which adjustment is possible in both directions,such that a tensile member can be made at the target length, and lengthcorrection can be designed to be either shorter or longer. (For example,the cable length and bushing halves 92 in FIG. 15 can be configured tofirst target the nominal length, and adjustments can then be made to thecable by simply using shorter or longer bushing halves 92. It need notbe only adjustable in one direction as simplified in this disclosure.)

7. An embodiment in which the inventive process and length adjustmentcomponent is made to the strand or sub-rope of a larger tensile member.In most cases this would include similar length adjustment componentswith all or most of the loaded subcomponents. This can be used tobalance subcomponents within a large assembly, just as if they wereindividual tension members requiring matched and stable lengths.

Although the preceding description contains significant detail, itshould not be construed as limiting the scope of the invention butrather as providing illustrations of the preferred embodiments of theinvention. Those skilled in the art will be able to devise many otherembodiments that carry out the present invention. Thus, the languageused in the claims shall define the invention rather than the specificembodiments provided.

Having described my invention, I claim:
 1. A method for producing asynthetic tensile member assembly having a predefined stable length,comprising: (a) providing a synthetic tensile member having a first endand a second end; (b) providing a first termination on said first end,said first termination having a first attachment reference; (c)providing a second termination on said second end, said secondtermination having a second attachment reference; (d) whereby saidsynthetic tensile member, said first termination, and said secondtermination are united to form said synthetic tensile member assembly;(e) preloading said synthetic tensile member assembly in order toproduce a stable overall length between said first and second attachmentreferences; (f) determining said stable overall length between saidfirst and second attachment references; and (g) determining an offsetdistance that is a difference between said predefined stable length andsaid stable overall length between said first and second attachmentreferences; and (h) adding a length adjustment component to said secondtermination, configured to add said offset distance to said secondtermination so that an overall length of said synthetic tensile memberassembly is equal to said predefined stable length.
 2. The method forproducing a synthetic tensile member as recited in claim 1, wherein: (a)said second termination includes a bearing surface; and (b) said lengthadjusting component is an extension bushing.
 3. The method for producinga synthetic tensile member as recited in claim 2, wherein: (a) saidsecond termination includes a shaft extending from said bearing surface;and (b) said extension bushing includes a through bore configured toslide over said shaft.
 4. The method for producing a synthetic tensilemember as recited in claim 3, wherein said shaft is a threaded shaft. 5.The method for producing a synthetic tensile member as recited in claim1, wherein: (a) said second termination includes a cross bore; and (b)said length adjusting component is a plug configured to fit within saidcross bore, said plug including an offset cross bore.
 6. The method forproducing a synthetic tensile member as recited in claim 1, wherein: (a)said second termination includes a posterior bearing surface where saidcable exits said termination; and (b) said length adjusting component isa bushing configured to bear against said posterior bearing surface. 7.The method for producing a synthetic tensile member as recited in claim6 wherein said bushing includes multiple pieces.